using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace DisplayMagicianShared.Windows
{
    public enum WIN32STATUS
    {
        ERROR_SUCCESS = 0,
        ERROR_ACCESS_DENIED = 5,
        ERROR_NOT_SUPPORTED = 50,
        ERROR_GEN_FAILURE = 31,
        ERROR_INVALID_PARAMETER = 87,
        ERROR_INSUFFICIENT_BUFFER = 122,
    }

    public enum DISPLAYCONFIG_DEVICE_INFO_TYPE
    {
        DISPLAYCONFIG_DEVICE_INFO_GET_SOURCE_NAME = 1,
        DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_NAME = 2,
        DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_PREFERRED_MODE = 3,
        DISPLAYCONFIG_DEVICE_INFO_GET_ADAPTER_NAME = 4,
        DISPLAYCONFIG_DEVICE_INFO_SET_TARGET_PERSISTENCE = 5,
        DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_BASE_TYPE = 6,
        DISPLAYCONFIG_DEVICE_INFO_GET_SUPPORT_VIRTUAL_RESOLUTION = 7,
        DISPLAYCONFIG_DEVICE_INFO_SET_SUPPORT_VIRTUAL_RESOLUTION = 8,
        DISPLAYCONFIG_DEVICE_INFO_GET_ADVANCED_COLOR_INFO = 9,
        DISPLAYCONFIG_DEVICE_INFO_SET_ADVANCED_COLOR_STATE = 10,
        DISPLAYCONFIG_DEVICE_INFO_GET_SDR_WHITE_LEVEL = 11,
    }

    public enum DISPLAYCONFIG_COLOR_ENCODING
    {
        DISPLAYCONFIG_COLOR_ENCODING_RGB = 0,
        DISPLAYCONFIG_COLOR_ENCODING_YCBCR444 = 1,
        DISPLAYCONFIG_COLOR_ENCODING_YCBCR422 = 2,
        DISPLAYCONFIG_COLOR_ENCODING_YCBCR420 = 3,
        DISPLAYCONFIG_COLOR_ENCODING_INTENSITY = 4,
    }

    public enum DISPLAYCONFIG_SCALING
    {
        DISPLAYCONFIG_SCALING_IDENTITY = 1,
        DISPLAYCONFIG_SCALING_CENTERED = 2,
        DISPLAYCONFIG_SCALING_STRETCHED = 3,
        DISPLAYCONFIG_SCALING_ASPECTRATIOCENTEREDMAX = 4,
        DISPLAYCONFIG_SCALING_CUSTOM = 5,
        DISPLAYCONFIG_SCALING_PREFERRED = 128,
    }

    public enum DISPLAYCONFIG_ROTATION
    {
        DISPLAYCONFIG_ROTATION_IDENTITY = 1,
        DISPLAYCONFIG_ROTATION_ROTATE90 = 2,
        DISPLAYCONFIG_ROTATION_ROTATE180 = 3,
    }

    public enum DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY
    {
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_OTHER = -1,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_HD15 = 0,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_SVIDEO = 1,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_COMPOSITE_VIDEO = 2,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_COMPONENT_VIDEO = 3,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_DVI = 4,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_HDMI = 5,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_LVDS = 6,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_D_JPN = 8,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_SDI = 9,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_DISPLAYPORT_EXTERNAL = 10,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_DISPLAYPORT_EMBEDDED = 11,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_UDI_EXTERNAL = 12,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_UDI_EMBEDDED = 13,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_SDTVDONGLE = 14,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_MIRACAST = 15,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_INDIRECT_WIRED = 16,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_INDIRECT_VIRTUAL = 17,
        DISPLAYCONFIG_OUTPUT_TECHNOLOGY_INTERNAL = unchecked((int)0x80000000),
    }

    public enum DISPLAYCONFIG_TOPOLOGY_ID
    {
        DISPLAYCONFIG_TOPOLOGY_INTERNAL = 0x00000001,
        DISPLAYCONFIG_TOPOLOGY_CLONE = 0x00000002,
        DISPLAYCONFIG_TOPOLOGY_EXTEND = 0x00000004,
        DISPLAYCONFIG_TOPOLOGY_EXTERNAL = 0x00000008,
    }

    public enum DISPLAYCONFIG_PATH
    {
        DISPLAYCONFIG_PATH_ACTIVE = 0x00000001,
        DISPLAYCONFIG_PATH_PREFERRED_UNSCALED = 0x00000004,
        DISPLAYCONFIG_PATH_SUPPORT_VIRTUAL_MODE = 0x00000008,
    }

    public enum DISPLAYCONFIG_SOURCE_FLAGS
    {
        DISPLAYCONFIG_SOURCE_IN_USE = 0x00000001,
    }

    public enum DISPLAYCONFIG_TARGET_FLAGS
    {
        DISPLAYCONFIG_TARGET_IN_USE = 0x00000001,
        DISPLAYCONFIG_TARGET_FORCIBLE = 0x00000002,
        DISPLAYCONFIG_TARGET_FORCED_AVAILABILITY_BOOT = 0x00000004,
        DISPLAYCONFIG_TARGET_FORCED_AVAILABILITY_PATH = 0x00000008,
        DISPLAYCONFIG_TARGET_FORCED_AVAILABILITY_SYSTEM = 0x00000010,
        DISPLAYCONFIG_TARGET_IS_HMD = 0x00000020,
    }

    public enum QDC
    {
        QDC_ALL_PATHS = 0x00000001, // Get all paths
        QDC_ONLY_ACTIVE_PATHS = 0x00000002, // Get only the active paths currently in use
        QDC_DATABASE_CURRENT = 0x00000004, // Get the current paths in the display database
        QDC_VIRTUAL_MODE_AWARE = 0x00000010, // Get the virtual mode aware paths
        QDC_INCLUDE_HMD = 0x00000020, 
    }

    public enum DISPLAYCONFIG_SCANLINE_ORDERING
    {
        DISPLAYCONFIG_SCANLINE_ORDERING_UNSPECIFIED = 0,
        DISPLAYCONFIG_SCANLINE_ORDERING_PROGRESSIVE = 1,
        DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED = 2,
        DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED_UPPERFIELDFIRST = DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED,
        DISPLAYCONFIG_SCANLINE_ORDERING_INTERLACED_LOWERFIELDFIRST = 3,
    }

    public enum DISPLAYCONFIG_PIXELFORMAT
    {
        DISPLAYCONFIG_PIXELFORMAT_8BPP = 1,
        DISPLAYCONFIG_PIXELFORMAT_16BPP = 2,
        DISPLAYCONFIG_PIXELFORMAT_24BPP = 3,
        DISPLAYCONFIG_PIXELFORMAT_32BPP = 4,
        DISPLAYCONFIG_PIXELFORMAT_NONGDI = 5,
    }

    public enum DISPLAYCONFIG_MODE_INFO_TYPE
    {
        DISPLAYCONFIG_MODE_INFO_TYPE_SOURCE = 1,
        DISPLAYCONFIG_MODE_INFO_TYPE_TARGET = 2,
        DISPLAYCONFIG_MODE_INFO_TYPE_DESKTOP_IMAGE = 3,
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_DEVICE_INFO_HEADER
    {
        public DISPLAYCONFIG_DEVICE_INFO_TYPE type;
        public int size;
        public LUID adapterId;
        public uint id;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_GET_ADVANCED_COLOR_INFO
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        public uint value;
        public DISPLAYCONFIG_COLOR_ENCODING colorEncoding;
        public int bitsPerColorChannel;

        public bool advancedColorSupported => (value & 0x1) == 0x1;
        public bool advancedColorEnabled => (value & 0x2) == 0x2;
        public bool wideColorEnforced => (value & 0x4) == 0x4;
        public bool advancedColorForceDisabled => (value & 0x8) == 0x8;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct POINTL
    {
        public int x;
        public int y;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct LUID
    {
        public uint LowPart;
        public int HighPart;

        public long Value => ((long)HighPart << 32) | LowPart;
        public override string ToString() => Value.ToString();
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_SOURCE_MODE
    {
        public uint width;
        public uint height;
        public DISPLAYCONFIG_PIXELFORMAT pixelFormat;
        public POINTL position;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_RATIONAL
    {
        public uint Numerator;
        public uint Denominator;

        public override string ToString() => Numerator + " / " + Denominator;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_2DREGION
    {
        public uint cx;
        public uint cy;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_DESKTOP_IMAGE_INFO
    {
        public POINTL PathSourceSize;
        public RECT DesktopImageRegion;
        public RECT DesktopImageClip;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_VIDEO_SIGNAL_INFO
    {
        public ulong pixelRate;
        public DISPLAYCONFIG_RATIONAL hSyncFreq;
        public DISPLAYCONFIG_RATIONAL vSyncFreq;
        public DISPLAYCONFIG_2DREGION activeSize;
        public DISPLAYCONFIG_2DREGION totalSize;
        public uint videoStandard;
        public DISPLAYCONFIG_SCANLINE_ORDERING scanLineOrdering;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_TARGET_MODE
    {
        public DISPLAYCONFIG_VIDEO_SIGNAL_INFO targetVideoSignalInfo;
    }

    [StructLayout(LayoutKind.Explicit)]
    public struct DISPLAYCONFIG_MODE_INFO_union
    {
        [FieldOffset(0)]
        public DISPLAYCONFIG_TARGET_MODE targetMode;

        [FieldOffset(0)]
        public DISPLAYCONFIG_SOURCE_MODE sourceMode;

        [FieldOffset(0)]
        public DISPLAYCONFIG_DESKTOP_IMAGE_INFO desktopImageInfo;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_PATH_SOURCE_INFO
    {
        public LUID adapterId;
        public uint id;
        public uint modeInfoIdx;
        public DISPLAYCONFIG_SOURCE_FLAGS statusFlags;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_PATH_TARGET_INFO
    {
        public LUID adapterId;
        public uint id;
        public uint modeInfoIdx;
        public DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY outputTechnology;
        public DISPLAYCONFIG_ROTATION rotation;
        public DISPLAYCONFIG_SCALING scaling;
        public DISPLAYCONFIG_RATIONAL refreshRate;
        public DISPLAYCONFIG_SCANLINE_ORDERING scanLineOrdering;
        public bool targetAvailable;
        public DISPLAYCONFIG_TARGET_FLAGS statusFlags;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_PATH_INFO
    {
        public DISPLAYCONFIG_PATH_SOURCE_INFO sourceInfo;
        public DISPLAYCONFIG_PATH_TARGET_INFO targetInfo;
        public DISPLAYCONFIG_PATH flags;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct DISPLAYCONFIG_MODE_INFO
    {
        public DISPLAYCONFIG_MODE_INFO_TYPE infoType;
        public uint id;
        public LUID adapterId;
        public DISPLAYCONFIG_MODE_INFO_union info;
    }

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    public struct DISPLAYCONFIG_GET_SOURCE_NAME
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
        public string viewGdiDeviceName;
    }

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    public struct DISPLAYCONFIG_TARGET_DEVICE_NAME_FLAGS
    {
        public uint value;
    }

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    public struct DISPLAYCONFIG_GET_TARGET_NAME
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        public DISPLAYCONFIG_TARGET_DEVICE_NAME_FLAGS flags;
        public DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY outputTechnology;
        public ushort edidManufactureId;
        public ushort edidProductCodeId;
        public uint connectorInstance;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 64)]
        public string monitorFriendlyDeviceName;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
        public string monitorDevicePath;
    }


    [StructLayout(LayoutKind.Sequential)]
    internal struct DISPLAYCONFIG_GET_TARGET_PREFERRED_NAME
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        public uint Width;
        public uint Height;
        public DISPLAYCONFIG_TARGET_MODE TargetMode;
    }

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    internal struct DISPLAYCONFIG_GET_ADAPTER_NAME
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
        public string AdapterDevicePath;
    }

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    internal struct DISPLAYCONFIG_SUPPORT_VIRTUAL_RESOLUTION
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        [MarshalAs(UnmanagedType.U4)]
        private uint DisableMonitorVirtualResolution;

        public bool IsMonitorVirtualResolutionDisabled
        {
            get => DisableMonitorVirtualResolution > 0;
        }

    }

    [StructLayout(LayoutKind.Sequential)]
    internal struct DISPLAYCONFIG_SET_TARGET_PERSISTENCE
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        [MarshalAs(UnmanagedType.U4)] 
        public uint BootPersistenceOn;

        public bool IsBootPersistenceOn
        {
            get => BootPersistenceOn > 0;
        }

    }

    [StructLayout(LayoutKind.Sequential)]
    internal struct DISPLAYCONFIG_GET_TARGET_BASE_TYPE
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        [MarshalAs(UnmanagedType.U4)] 
        public DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY BaseOutputTechnology;

    }


    [StructLayout(LayoutKind.Sequential)]
    internal struct DISPLAYCONFIG_SET_ADVANCED_COLOR_STATE
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        [MarshalAs(UnmanagedType.U4)]
        public uint EnableAdvancedColor;

        public bool IsAdvancedColorEnabled
        {
            get => EnableAdvancedColor > 0;
        }

    }

    [StructLayout(LayoutKind.Sequential)]
    internal struct DISPLAYCONFIG_SDR_WHITE_LEVEL
    {
        public DISPLAYCONFIG_DEVICE_INFO_HEADER header;
        // SDRWhiteLevel represents a multiplier for standard SDR white
        // peak value i.e. 80 nits represented as fixed point.
        // To get value in nits use the following conversion
        // SDRWhiteLevel in nits = (SDRWhiteLevel / 1000 ) * 80
        public ulong SDRWhiteLevel;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct RECT
    {
        public int left;
        public int top;
        public int right;
        public int bottom;
    }

    
    class CCDImport
    {
        // GetDisplayConfigBufferSizes
        [DllImport("user32")]
        public static extern int GetDisplayConfigBufferSizes(QDC flags, out int numPathArrayElements, out int numModeInfoArrayElements);

        // QueryDisplayConfig
        [DllImport("user32")]
        public static extern int QueryDisplayConfig(QDC flags, ref int numPathArrayElements, [In, Out] DISPLAYCONFIG_PATH_INFO[] pathArray, ref int numModeInfoArrayElements, [In, Out] DISPLAYCONFIG_MODE_INFO[] modeInfoArray, out DISPLAYCONFIG_TOPOLOGY_ID currentTopologyId);

        [DllImport("user32")]
        public static extern int QueryDisplayConfig(QDC flags, ref int numPathArrayElements, [In, Out] DISPLAYCONFIG_PATH_INFO[] pathArray, ref int numModeInfoArrayElements, [In, Out] DISPLAYCONFIG_MODE_INFO[] modeInfoArray, IntPtr currentTopologyId);

        // DisplayConfigGetDeviceInfo
        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_GET_SOURCE_NAME requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_GET_TARGET_NAME requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_GET_TARGET_PREFERRED_NAME requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_GET_ADAPTER_NAME requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_SET_TARGET_PERSISTENCE requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_GET_TARGET_BASE_TYPE requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_SUPPORT_VIRTUAL_RESOLUTION requestPacket);

        /*[DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_SET_SUPPORT_VIRTUAL_RESOLUTION requestPacket);
*/
        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_GET_ADVANCED_COLOR_INFO requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_SET_ADVANCED_COLOR_STATE requestPacket);

        [DllImport("user32")]
        public static extern int DisplayConfigGetDeviceInfo(ref DISPLAYCONFIG_SDR_WHITE_LEVEL requestPacket);

        // DisplayConfigSetDeviceInfo
        [DllImport("user32")]
        public static extern int DisplayConfigSetDeviceInfo( ref DISPLAYCONFIG_SET_TARGET_PERSISTENCE targetPersistence );

        // Have disabled the DisplayConfigSetDeviceInfo options except for SET_TARGET_PERSISTENCE, as per the note
        // from https://docs.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-displayconfigsetdeviceinfo
        // "DisplayConfigSetDeviceInfo can currently only be used to start and stop boot persisted force projection on an analog target."
        /*[DllImport("user32")]
        public static extern int DisplayConfigSetDeviceInfo( ref DISPLAYCONFIG_SUPPORT_VIRTUAL_RESOLUTION targetSupportVirtualResolution );*/

        // SetDisplayConfig
        [DllImport("user32")]
        public static extern int SetDisplayConfig( [In] uint pathArrayElements, [In] DISPLAYCONFIG_PATH_INFO[] pathArray, [In] uint modeInfoArrayElements, [In] DISPLAYCONFIG_MODE_INFO[] modeInfoArray, [In] QDC flags );

    }
}